• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.4
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• pp.67-75
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• 1998

In general, Evoluationary Algorithm(EAs) are refered to as methods of population-based optimization. And EAs are considered as very efficient methods of optimal sytem design because they can provice much opportunity for obtaining the global optimal solution. This paper presents a co-evolution scheme of artifical neural networks, which has two different, still cooperatively working, populations, called as a host popuation and a parasite population, respectively. Using the conventional generatic algorithm the host population is evolved in the given environment, and the parastie population composed of schemata is evolved to find useful schema for the host population. the structure of artificial neural network is a diagonal recurrent neural netork which has self-feedback loops only in its hidden nodes. To find optimal neural networks we should take into account the structure of the neural network as well as the adaptive parameters, weight of neurons. So we use the genetic algorithm that searches the structure of the neural network by the co-evolution mechanism, and for the weights learning we adopted the evolutionary stategies. As a results of co-evolution we will find the optimal structure of the neural network in a short time with a small population. The validity and effectiveness of the proposed method are inspected by applying it to the stabilization and position control of the invered-pendulum system. And we will show that the result of co-evolution is better than that of the conventioal genetic algorithm.

• Proceedings of the Korea Information Processing Society Conference
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• 2015.10a
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• pp.983-986
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• 2015

물리적, 논리적 공간에서 다양한 오브젝트들이 상호작용할 수 있게 되고, 오브젝트에 탑재되는 소프트웨어가 고도화 됨에 따라 엔지니어가 관리 가능한 수준의 시스템 제어가 힘들어지고 있다. 이런 복잡한 시스템의 자율적인 관리를 위해 다양한 상황에 대응 가능한 자가적응성이 요구된다. 자가적응형 소프트웨어는 대상 시스템의 목표나 QoS를 만족할 수 있도록 런타임에 스스로를 변화 시킬 수 있는 능력을 가진 소프트웨어이다. 이러한 소프트웨어는 고도화된 시스템의 관리에 있어서 엔지니어의 부담을 경감시킬수 있다. 본 논문에서 제안하는 선행적 자가적응형 시스템은 도로망과 같은 주기적 특성을 가진 시스템에서 시스템이 직면하는 상황을 사전에 예측하여 미리 대응할 수 있는 시스템이다. 이는 기존에 반응적으로 대응했던 시스템들이 적용한 정책의 효과를 보기까지 낭비되는 시간을 고려하여 해당 지연시간동안에 시스템의 목표나 QoS가 하락하는 상황을 미연에 방지할 수 있다. 본 시스템의 적용분야로 지능형교통체계를 사용하였으며, 도로망 전체에서 정체 발생빈도와 평균 이동속도 그리고 단위길이당 운행시간을 평가항목으로 사용하고, 대상 도로망 전체적인 최적화를 목표로 한다.

• Journal of Soil and Groundwater Environment
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• v.26 no.5
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• pp.60-76
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• 2021

The concept of resilience seems applicable for sustainable groundwater management. The resilience is broadly defined as the ability of a system to resist changes by external forces (EFs), and has been used for disaster management and climate change adaptation, including the groundwater resilience to climate change in countries where groundwater is a major water resource, whereas not yet in the geological society of South Korea. The resilience is qualitatively assessed using the absorptive, adaptive, and restorative capacity representing the internal robustness, self-organization, and external recovery resources, respectively, while quantitatively using the system impact (SI) and recovery effort (RE). When the groundwater is considered a complicated system where physicochemical, biological, and geological components interact, the groundwater resilience can be defined as the ability of groundwater to maintain the targeted quality and quantity at any EFs. For the quantitative assessment, however, the resilience should be specified to an EF and measurable parameters should be available for SI and RE. This study focused on groundwater resilience to two EFs in urban areas, i.e., pollution due to land use change and groundwater withdrawal for underground structures. The resilience to each EF was assessed using qualitative components, while measurements for SI and RE were discussed.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.37 no.5
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• pp.46-55
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• 2000

This paper presents a direct adaptive control of robot system using chaotic neural networks and PD controller. The chaotic neural networks have robust nonlinear dynamic characteristics because of the sufficient nonlinearity in neuron itself, and the additional self-feedback and inter-connecting weights between neurons in same layer. Since the structure and the learning method are not appropriate for applying in control system, this neural networks have not been applied. In this paper, a modified chaotic neural networks is presented for dynamic control system. To evaluate the performance of the proposed neural networks, these networks are applied to the trajectory control of the three-axis PUMA robot. The structure of controller consists of PD controller and chaotic neural networks in parallel for conforming the stability in initial learning phase. Therefore, the chaotic neural network controller acts as a compensating controller of PD controller.

• Journal of Power Electronics
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• v.13 no.1
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• pp.139-160
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• 2013

In this paper, an intelligent robust control system (IRCS) for precision tracking control of permanent-magnet synchronous motor (PMSM) servo drives is proposed. The IRCS comprises a recurrent wavelet-based interval type-2 fuzzy-neural-network controller (RWIT2FNNC), an RWIT2FNN estimator (RWIT2FNNE) and a compensated controller. The RWIT2FNNC combines the merits of a self-constructing interval type-2 fuzzy logic system, a recurrent neural network and a wavelet neural network. Moreover, it performs the structure and parameter-learning concurrently. The RWIT2FNNC is used as the main tracking controller to mimic the ideal control law (ICL) while the RWIT2FNNE is developed to approximate an unknown dynamic function including the lumped parameter uncertainty. Furthermore, the compensated controller is designed to achieve $L_2$ tracking performance with a desired attenuation level and to deal with uncertainties including approximation errors, optimal parameter vectors and higher order terms in the Taylor series. Moreover, the adaptive learning algorithms for the compensated controller and the RWIT2FNNE are derived by using the Lyapunov stability theorem to train the parameters of the RWIT2FNNE online. A computer simulation and an experimental system are developed to validate the effectiveness of the proposed IRCS. All of the control algorithms are implemented on a TMS320C31 DSP-based control computer. The simulation and experimental results confirm that the IRCS grants robust performance and precise response regardless of load disturbances and PMSM parameters uncertainties.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.538-541
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• 2006

Recently researches of P2P media streaming have been actively published, but the research what kind of P2P overlay networks are better to delivering media data has not been attended. This paper designs a P2P streaming media system model. In this system, we constructs a Half-Structure P2P overlay protocol based on node's capability as the infrastructure of streaming application, which utilizes the heterogeneity of the nodes to maintain topology, presents a active contents diffusing algorithm and Two-stage search algorithm, make it possible for nodes in P2P system to collect information according their capacity and reduces the number of forwarding packet compared with flooding. Also, we give an optimal scheme to scheduling media data.

• Journal of Korean Academy of Nursing
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• v.9 no.2
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• pp.49-61
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• 1979

A review of this literature and discussions reveal a development of ideas concerning the elements of nursing models. The elements of a nursing model are the nurses view of the human being, nursing's goal, and nursing activities. It has long been recognized that human beings, at one time or another, require nursing care. Varieties of literature were reviewed in regard to the human being as recipient of nursing care through the theory development in nursing. Florence Nightingale initiated the modern era of nursing and described more clearly man as the recipient of nursing care. She looked at man as responding to the laws of nature whether the person was healthy or sick. Henderson added to Nightingale's concept of man , the recipient of nursing care by emphasizing that man is a whole, complete, and independent being. Her view is further specified by her enumeration of the activities the human being must perform. Johnson has developed a very comprehensive view of man as the recipient of nursing care. Man is a behavioral system which has a tendency to achieve and maintain stability in patterns of functioning. Like Nightingale, Johnson sees that similar patterns occur in both health and illness. Johnson postulates that the whole behavioral system of the human is composed of eight sub-systems: affiliative, achievement, aggressive, dependency, eliminative, ingestive, restorative, sexual. Roger's main contribution to the development of nursing models was her emphasis upon unitary man. She pointed out that man is a unified whole, possessing his own integrity and manifesting characteristics that“are more than and different from the sum of his parts.”Rogers focuses on the life processes of the human and points out that these processes have the following characteristics. Wholeness, openness, unidirectionality, pattern and organization, sentence, and thought. According to Roy, man is a biopsychosocial being in constant interaction with a changing environment. To cope with this changing environment, man has certain innate and acquired mechanisms. Man's ability to respond positively or to adapt, depends upon the degree of the change taking place and the state of the person coping with the change. When she analyzes man as an adaptive organism she further describes man as being composed of four adaptive modes: physiological needs, self-concept, role function, and interdependence. Based on the literary review through the theory development in nursing, general approach by a unified nursing model to a view of the recipient of nursing care may be stated as follows: Man is a unified whole composed of subsystems with a flexible and normal line of defense; his internal regulating mechanisms help him to cope with a changing environment; he functions by the principles of homeodynamics.

• Journal of Korea Water Resources Association
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• v.54 no.7
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• pp.475-484
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• 2021

The optimal design for water distribution system (WDS) is not only satisfying the minimum required water pressure of the nodes, but also minimizing pipe cost, etc. The number of designs of WDS increases exponentially due to the arrangement of various pipes. Various optimization algorithms were applied to propose an optimized design of WDS. In this study, Modified Hybrid Vision Correction Algorithm (MHVCA) with improved self-adapting parameter was applied to optimal design of WDS. The performance was improved by changing the Hybrid Rate (HR) of the existing Hybrid Vision Correction Algorithm (HVCA) to nonlinear HR. To verify the performance of the proposed MHVCA, it applied to mathematical problems consisting of 2 and 30 decision variables and constrained mathematical problems. In order to review the application results of MHVCA, it was compared with Harmony Search (HS), Improved Harmony Search (IHS), Vision Correction Algorithm (VCA) and HVCA. Finally, MHVCA was applied to the optimal design problem of WDS and the results were compared with other algorithms. MHVCA showed better results than other algorithms in mathematical problems and WDS problem. MHVCA will be able to show good results by applying to various water resource engineering problems as well as problems applied in this study.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.2C
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• pp.112-118
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• 2011

In this paper, we conduct an objective performance analysis of the crosstalk cancellation scheme studied in [11]. While the conventional scheme is only applicable to a listener on the optimal listenable region (sweetspot), the space skew/crosstalk cancellation (SS/CC) scheme in [11] can mitigate crosstalk regardless of the listener's position by using listener position tracking (LPT) system. The SS/CC scheme is composed of two parts: LPT-based SS and CC parts. In this paper, the SS/CC scheme is evaluated by some criteria such as follows: condition number, and the balance characteristic, its root mean square error, and running average.

• Journal of Korean society of Dental Hygiene
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• v.9 no.4
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• pp.633-643
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• 2009

Objectives : This study is aimed to help the dental hygiene department students to improve their adaptive ability to the field work by letting them know the performing levels required of the job world, by renovating the knowledge-centered curriculum, and by finding out the core competencies needed for successfully performing their duties and tasks in the work field. Methods : The survey tool was recomposed through the examination of the preceeding studies on basic vocational competencies and skills, and the survey has been done to 200 dentists in Seoul and Gyunggi provice. Results : 1. As for the job-getting routs, 35.1% of them finds their jobs through the job portal sites, and 21.3% through the recommendation by professors. So we can see the meaningful difference in the employment ways. 2. Dental hygiene clinics think that the purpose of their cooperation with the colleges is mainly to secure human resources by requiring the colleges to give field-centered education the colleges through. 3. The clinics for dental hygienic students' field learning have a great power for hiring the students. So it is necessary to set up a good management system of the clinics for dental hygienic students' field learning in order to reinforce the students' competitive power in getting jobs. 4. The priorities in basic working abilities needed for the task performance are in the order of vocational responsibility, self-managing & developing ability, interpersonal skill, and problem solving ability. 5. The core competencies required of those who graduate from dental hygiene school show the following scores by Likert measurement; good personality and vocational consciousness 2.16(${\pm}.677$), understanding power of major-related knowledge 2.19(${\pm}.723$), field adapting ability 2.31(${\pm}.748$), get-along-with ability 2.32(${\pm}.799$), interpersonal skill 2.42(${\pm}.768$), and self-development ability such as getting certificates 2.43(${\pm}.729$). Among the core competencies, the only meaningful factor which influences on their satisfaction measurement has been identified as the professional ability related to the major. Conclusions : The results suggest that the knowledge and skill related to the major are core competencies of able human resources and closely related with the professionality of the job, and so they are very important. However, job basic abilities are also proved to be important, which reinforce the students' activeness, self-regulation, and creativeness, and help them to pursue their lasting growth in their abilities.